Radio apparatus



June 6, 1950 D. H. CAMPBELL ETAL RADIO APPARATS 9 Shets-Sheet 1 Filed June 21, 1946 lune 6, 1950 H. CAMPBELL EI'AL RADIO APPARATS 9 SheetsSheet 2 Filed June 21, 1946 June 6, 1950 D H. CAMPBELL ElAL RADIO APPARATS 9 SheetsSheet 4 Filad June 21, 1946 June 1950 D. H. CAMPBELL ETAL 2,510,681

' RADIO APPARAIUS Filed June 21, 1946 9 SheetsSheet 6 June 6, 1950 D. H. CAMPBELL ETAL RADIO APPARATS 9 Sheets-Shec 7 Filed June 21, 1946 mJLaricn J1me 1950 D. H. CAMPBELL EIAL 2,510,631

;RADIO APPARATS 9 Sheets-Sheet 8 Filed June 21, 1946 bel l.

June 6, 1950 D. H. CAMPBELL ETAL RADIO APPARATS 9 Sheets,Sheet 9 Filed June 21, 1946 Patented June 6, 1950 UNITED .STATES PATENT OFFICE Larkin, Lynnfield, Mass., assignors 10 National Company, :Inc., Malden, Mass., a corporation :of

.Massachusetts Application J une 21, 1946, 'SerialNo. 678,226

20 -Claims. 1

This invention relates to radio apparatus and in particu-lar to a cabinet for housing such a mechanismas-a-raio receiver, and theobjectis to provide a sturdy cabinet for housing a machanism of that nature wherein it WH be readily accessible for inspection, -servicing or repair as reqnired and which -can be manipulated easily and safely.

The arrangement in particular provides f! compactly housing a mechanism of the type referred to of substantial size and which might be -considered as, -at most, senti-portable. It has been found particularly -useful in installations on ships Which *may -be rcfliing or "pitching =vvhen it is necessary to have access to the mechanism refered to *so that it is desirable that the parts be firmly held in the various positions which they mayassume and be capable of -firm manua] contrdl as they are moved from one position to another. The features of construction *whereby such desirable -results are attained wil1'be referred to as the-description proceeds and will be further understood Stherefrom.

Our invention will be we1l Understood 'b reference 'to the fo1lowing description of the illustrative embodiment thereof shownby Way of example in the accompanying drawings. In these drawings represerflaing a cabinet for housing a radio transmitter and receiver the various clements iorming portions of the .electronic :system have .generally been .omitted. F'urthermore, to avoid confusion many of the figures show merely certain of the parts, adjacent parts being omitted. We have not attemptedin the following brief description of the figuresof.thedrawings to characterize or refer tosuch omissions as they Will be obvious to one amiliar with the reading of drawings.

Fig. 1 is a front elevation -of the cabinet and shows the panel of the radio installation, ornitting the various accessories:snchas contre] knobs, indicating instruments and the :like, which ordinarilyappear on:such a panel although zthe positions where some-of these parts are mounted are indicated;

Fig. 2 is acide elevation;

Fig. 3 is a side elevation :of :the panel and attached chassis removed f-nom the .casing :proper which encloses the chassis;

.4 is a-section of the .neaI-er side:of the cabinet, viewing Fig. :3, on the Iine 44 of that :1igure;

Fig. 5 lis a side elevation :onga smafler :scalehowing :bhB chassis withdxaxvn irom :the cabinet I p Fig. 6 is a similar view showing the chassis tilted;

. omitted, in general corresponding to a longitudimai section just outward-oi one oi theha1dles on the=panel and showirig the-cabinet SIightlyopened or ajar;

Fig. 12 is a section'looking down in Fig. 11 from a Diane just below the top 'wall of "the cabinet proper;

Fig. 13 a rear vieW of the portion of the drawer front or panel as seen froni the right in Fig. 11;

Fig. 14 is a, fragmentarylongitudinal section on a larger scale of the pivot latch controlling *means which appears about centrally of Fig. 11;

Fig. 15 is 9. section on a'larger scale on line l5l5 of Fig. 11;

Fig. 16 is a section on the'fine l6l-G of Fig. :15;

Fig. 17 is a view corresponding =to aportion of Fig.'l1 with the parts ina,-difierent position;

Fig. 18 is a longitudinal section ta;ken in a vertical plane *jnst 'inwardly -of the further Wall '0f the casing, the-auxiliary casihgor blisterhiflg omitted;

Fig. 18a -is a side -elevation partly brok n away of the blister winch, relative'to Fig. 18, isshoW-n adjacent the position Which it odcupies When assembled With the casihg;

Fig. 19is a section on the =line l9l9 0]? Fig. 18;

Fig. 20 is a -ragmentarydetail -Chiefi in levatioi1 illustrating the parts which are located at the upperright-hand corner of Fig. 19;

Fig. 21 is a section on an enlarged scale on the line 2!2l of Fig. 19;

Fig. 22 is a transverse section of the -ca;binet proper just iorwardl of its rear wali;

Fig. 23 corresponds to-the loWer part of "Figfi22 and shows the parts in a diierent position of adjustment;

Fig. 24 i-Sajt0p plan viewof the front endof the cabinet -shoWing the panel slightly -withdrawn irom :the oasing;

Fig. '25 is arear elevation cf a portion of the panel as seenfr0m the line 12 5 25 :01? Fig. :24;

Fig. 26 is:a.section 1mthe ;line 26- 25 o Fig. 24'; and

.Fig. 2.! :is a:similar:view showingdsirepafits closed together.

Before proceeding to a detailed description of the drawings, a brief preliminary outline may facilitate understanding. In general the construction resembles a drawer of the so-called slide type commonly used in filing cabinets and (see Figs. 2 and 5) comprises a casing 40 corresponding to the drawer casing. The chassis 42 of the radio mechanism telescopes therein in the manner of the drawer proper and the casing is closed by the front panel 5 1 of the radio mechanism which as usual mounts various control mechanisms and indicating instruments and which corresponds to the drawer front and which projects, as seen in Fig. 6, around the chassis as is common in certain types of drawers. As in the slide type of drawer, the chassis may be entirely withdrawn from within the casing 69 to a supported posi tion exterior of the casing, as illustrated in Fig. 5.

In the embodiment of the invention shown an auxiliary casing 45 is mounted at the rear end of the casing il. This auxiliary casing is colloquially termed a blister and, for convenience, that word will be used when it becomes necessary to refer to it in the detailed description. Herein the blister is secured over an opening in the rear wall of the casing 35, the parts being shown separated in Figs. 18 and 18a, the blister being shown in Fig. 180, in a position relative to the casing in Fig. 18 corresponding to a slight displacement of the blister to the right from the position it would occupy if assembled with the casing Electric conductors lead to the mechanism in the cabinet through the rear and in the present instance may be attached by suitable couplings (not shown) to nipples 41 carried by the wall of the blister (which in the case of the particular construction illustrated contained electric filtering devices) and from the front or inner face of which the various electric conductors are lad, grouped into tvvo cables 38, one at each side of the casing. These cables de may be supported along the inner side of the top or ceiling of the cabinet to a point adjacent the front thereof, as indicated in Figs. 5, 6, 7 and 8, and then are looped in planes near the side walls about pulleys 55 which serve to control the slack of the cables in .a manner to be described as the chassis is moved in and out. The cableg are clamped by clamps 52 to the sides of the chassis at points adjacent the centers 54 on which it is trunnioned for movements between the positions illustrated in Figs. 5 and 6, as hereinafter more fully described, and extend hence to suitable banks or gangs of connectors from which the various wires lead to mechanisms carried by the chassis or panel. No attempt has been made to show the last mentioned connections in the drawings. For the purpose of understanding the construction under consideration we might consider that the cable ended at the point .52.

There will neXt be described the slide mechanism by which the chassis is supported and permitted to move from within the casing 45 to the position of Fig. 5. Reference will be made particularly to Figs. 9, and 17. It Will be understood that the construction shown in Fig. 9 is duplicated on the other side of the cabinet. Referring to that figure, the inner face of the vertical wall of the casing carries upper and lower tracks 56 facing toward each other and guiding the wheels or rollers 58 of an intermediate slide 60 and between these rollers is mounted the fianged channel 52 constituting a side element of a carriage from which the chassis is supported. Herein brackets 64 on these elements 52, which brackets .re broken away in Fig. 9 but may be seen complete in Figs. 5 and 6, support the trun nions 65 at the pivotal axis 54 previously referred to, by which trunnions the chassis 42 is pivotally mounted. In Figs. 5 and 6 the numeral 54 is applied to a screw which taps into the trunnion proper (sec Fig. 9) and releasably retains the trunnion in its bearing. The center of gravity of the trunnion-supported parts is forward of this axis and in the horizontal position of the chassis it rests on cross-bar 66 which joins the forward ends of the two channels 62, being received between two centering projections 61 thereon having conical upper portions cooperating with the adjacent lower corners of the chassis when it is swung downwardly from the elevated position of Fig. 6 to the position of Fig. 5 and Fig. 9.

When the chassis has been completely withdrawn to the position of Fig. 5, preferably the slide is automatically locked in the extended position, herein by means of the pivoted paWl 68 housed within the concavity of channel 62. The point of this pawl drops down behind a projection on the intermediate slide 60, thus holding the slide mechanism iatched in the extended position of Fig. 5 until the pawl is released. The arrangements herein provided for effecting this release Will be later described.

Referring now to Figs. 5 and 6, the chassis when withdrawn from the casing may take three positions without removing it from its carriage, the horizontal position shown in Fig. 5, the vertical position illustrated in full lines in Fig. 6 and the diagonal position illustrated in dotted lines in that figure. The vertical position gives ready access to the bottom of the chassis for work thereon and the diagonal position is designed to give the maximum space between the top of the chassis and the top wall of the open end of the casing Ml for access to the interior of the casing. As best seen in Fig. 2, the bracket 64 carries a sector m with locking notches adapted to be engaged by a releasable latch bolt 72 slidably rnounted on the side of the chassis and manipulated as hereinafter described to hold the chassis locked in any one of its several angular positions.

Each cable 48 must be long enough to reach to its point of anchorage 52 on the chassis when v the latter is withdrawn to the positions of Figs.

5 and 6. Means are provided for controlling the slack of the cable so it is, as it were, neatly coiled up in a vertical plane adjacent the side walls of the cabinet proper 4 and automatically disposed of when the parts are returned to the closed position. The bight of the cable as already described is trained about the pulley 50 which is mounted on the intermediate slide Sil. Referring to Fig. 18 in connection with Fig. 9, it Will be seen that this intermediate slide carries a pinion fl, herein coaxial with the lower roller 58, which gears with a downwardly presented rack 16 on the carriage slide 62 and an upwardly presented fixed rack 18 associated with the parts which form the lower track 56. Thus When the chassis carriage 62 is drawn out, the intermediate slide 56 moves proportionately thereto, in this instance one-half of the distance. The pulley thus is in effect the moving pulley of a so-called runner tackle of which the standing part is the point of anchorage of the cable to the roof or ceiling of the cabinet 40 and the hauling portion or fall is connected to the moving chassis. With the chassis extended, the pulley has the position of Fig. 8 and as a given length of cable is released by the retreating chassis moving toward the the thurnb lever is rocked, the bolt 12 is retracted by the screw action of the spiral groove to ree the bolt from the sector 10 and permit the chassis to be swung about its trunmons by force applied at the handles 86 which remain securely gripped at all times.

Referring particularly to Figs. 11 and 15, it will be seen that the end of shaft 98 opposite the crank disc 96 has a halfround extension [40 which opposes a rounded abutment member M2 at the open front of the casing. When the front of the cabinet is closed and the bolts 88 engaged with their keepers 92, the fiat surface lies immediately adjacent this abutment. Now, if the crank dise is rocked to release the bolts, this fiat surface acts in the manner of a oam against the abutment #2 to move the panel toward the left, viewing Fig. 11, setting it ajar ready for further withdrawal. This action is of particular advantage as contrasted with merely pulling the cabinet open when the parts are constructed in the manner illustrated more particularly in Figs. 24 through 27 which will next be described.

Referring to Fig. 26 (ses also Figs. 22 and 23), the casing 40 is a box of sturdy yet relatively thin meta1 of generally rectangular form and with an open end while the panel 44 is shaped from similar metal with a short fiange and might be said to be a similar box ocf shallow depth. The extended dimensions of these parts, particularly in the case of the casing 4l), provide an opportunity for flexure or warpage and it is desirable that the surfaces should meet accurately in a butt joint, as illustrated in Fig. 27. There are herein shown secured to the inner faces of these opposed edges of casing and panel respectively angle irons l43 and 145 (sec Figs. 26 and 27) having their horizontal flanges notched to provide tooth-like projections M and [46 in staggered or alternating relation and respectively adapted to enter beneath the opposed edge o the other part between the projections therefrom when the two parts are closed together in the position of Fig. 7 to support the opposed edges and bring them into alignment. It will be seen from Fig. 25 that the ends of these projections are sorne- What wedge-shaped or pointed so that they enter easily and if the parts are somewhat out of lime bring them into and hold them in accurate alignment. There is thus an interlocking engagement of the casing 40 and its closure formed bY the panel 44, as shown in Fig. 26, although the parts are exteriorly smooth, andwhile the final fit is a tight one, it does not prevent the ready approximation of the parts.

For electrical reasons in the case of such an apparatus as a radio receiver it is desirable that the panel 44 have good electrical contact with the casing 40 to provide a grounding connection. Herein we show in the spaces between the teeth E46 and opposing the teeth I44 angular members l48 which may' be of nickel-plated brass having resiliently yieldable, horizontally extending tongues over which the teeth M may ride when the parts are approximated to the position of Fig. 26 desirably with some downward fiexure of the tongues t insure a ti ght contact.

When the blister 46 is used, as seen in Fig. 2, it may be in the form of a basin-like shell (sec Fig. 18a) having a peripheral fiange Iu, the body of the shell passing through opening l52 in the rear wall of the casing 40 with the flange l50 engaging the inner surface of the wall around the periphery of the opening. The front of the basin-like casing may be closed by a cover plate 154 provided with handles l56 for manipulating the same. When the chassis is withdrawn and tipped to the dotted lime position of Fig. 6, a maximum opening at the top between the same and the front end of the casing 411 is provided to permit the blister to be withdrawn or to be inserted in position. T0 look it in this position means are provided which may be manipulated from adjacent the open front of the casing. The mechanism herein disclosed for this purpose is most clearly illustrated in Figs. 18 through 23. The flange [5E3 of the blister and the overlying portion of its cover are provided with notches l53 which are adapted to pass the projections l6!) oi locking bars l62 slidabls mounted on the rear wall of the cabinet et the top and bottom of the opening in the mariner illustrated in Fig. 23. After the flange has been moved away from the reader, viewing Fig. 23, past these projections, if the bars 562 are then shifted to the position shown in Fig. 22 the projections l60 will overlie the fiange and look it against the margin of opening l52. The mechanism herein shown whereby these bars are operated will next be described.

Viewing Fig. 22, it will be seen that there is an upper and lower bar at either side of the center and each pair is operated by means disposed inwardly of the adjacent side wall of the casing 40 and but one of these means needs to be described in detail. In Fig. 18 we are viewing the mechanism on the urther side of the cabinet. The bars [62 are slidably mounted by pin and slot connections E63 (Figs. 22 and 23) on the rear wall of the casing 40 and are adapted to be reciprocated horizontally, viewing Fig. 22, by a crossbar l6 i connecting the ends Which are adjacent the casing wa1l. This cross-bar I64 (see Fig. 20) has a slot me in which works a pin on a crank arm i 66, the mechanism being of the type known as a Scotch yoke. As the crank arm swings, the cross-bar I6 is reciprocated and with it the locking bars H52. The shaft ll Which carries the crank arm l68 extends along the adjacent side of the casing l (see Fig. 19) and is secured by a coupiing sleeve H2 to a short coaxial shaft [14 having an angularly bent crank arm 116 for turning the same, Which arm normally lies fiat against the side of the casing. As is apparent from Fig. 20, a movement of the crank l68 through effects the maximum reciprocating movement of the locking bars 52. It would not be desirable inadvertently to move the crank past center and inadvertently return the bars to a locking position when it was desired to release them. IIowever, a movement of the operating lever li6 through 180 is desirable so that at either extreme of its movement this may lie conveniently out of the way parallel to the side of the casing. Lost motion between shats l'l0 and 114 may therefore be provided by suitable means such, for example, as that shown in Fig. 21 wherein the end of shaft Il!) within the sleeve Il2 which is secured thereto has a quadrantal projection ii8 extending through of angle which is overlapped by a segmental extension of like angular extent on the driving shaft IM. These define between them an empty space of 90 angle. This arrangement permits the latter to turn 90 of which is lost motion relative to shaft l'fll and 90 of which turns the latter shaft. To hold arm ll6 from -casual displacement from the position of Figs. 18 and 19 a catch may be provided, herein in the form of a leaf spring [82 having a hole in its end (sec Fig. 18) receiv ing the extreme lower end of the arm 116. This 9 spring may be easily pressed down to free the arm when it is desired to utilize it as a. means of rocking shait [10 for moving the locking bars [62 which retain the blister in position.

We are aware that the invention may be embodied in other specifio forms without departing from the spirit or essential attributes thereof, and we therefore desire the present embodiment to be considered in all rspects as illustrative and and not restrictive, as is in fact clear in several matters from the description itself. Reference is to be had to the appended claims to indicate those principles of the invention exemplified by the particular embodiment described and which we desire to secure by Letters Patent.

We claim:

1- A radio apparatus comprising a chassis and a casing telescopically associated in the manner of a drawer and its case, guideways in the casing, extension slides moving on the guideways, a chassis-supporting carriage movable on the slides, racks on the guide and the carriage and a connecting pinion rotatably mounted on the slide, interposed between said racks and meshing therewith, a pulley wheel on the slide and a flexible conductor extending between the chassis and a fixed point of the casing and looped about said pulley wheel.

2. A radio apparatus comprising a chassis and a casing With which the chassis is associated through an intermediate slide in the manner of an extension drawer, a flexible conductor extend ing between the movable chassis and a fixed point of the casing, a pulley about which the bight of the condur:tor is looped and means for advancing it difierentiafly to the chassis as the chassis is withdrawn from the casing to pay out the length of conductor, and means for retracting the pulley as the chassis is returned to take up the length of conductor so payed out.

3. A radio apparatus comprising a chassis and a casing within which it is telescopically mounted, a tackle within the casing the flexible element of which takle is a conductor extending between a fixed point of the casing and the chassis, the tackle including a movable pulley, and means for moving the pulley difierentially and proportionately to the movement of the chassis to take up and pay out the length of conductor intervening between said fixed point and the chassis as the chassis is nicved.

4. A radio apparatus comprising a chassis and a casing which telescopically receives it in the manner of a drawer, a flexible conductor extending within the casing extending between an interior point thereof and the chassis, a movable member within the casing about which the bight of the conductor is looped operatively associated With the chassis to be moved diierentially thereto as the chassis is moved in and out relatively to the casing to take up and pay out the length of conductor intervening between said interior point and the chassis.

5. A radio apparatus comprising a casing, a panel f0rming a closure therefor, a chassis projecting from the panel, trunnions on the chassis, et carriage having bearings for said trunnions thereby to support the chassis, telescopic extension devices for supporting the carriage from the interior walls of the casing, a sector on the carriage adjacent a trunnion, a bolt on the chassis coopera,ting with the sector for latching the chassis in selected positions of rotative adjustment, handles at the front of the panel having portiens for encirclement by the grasping fingers of the hands, a finger piece accessible to the thumb of a hand grasping a handle for movement by the thumb and connections between said finger piece and the bolt for shifting the latter responsively to movement of the former.

6. A radio apparatus comprising a casing, a panel forming a olosure therefor, a chassis projecting from the panel, a carriage on which the chassis is trunnioned, telescopic extension devices for supporting the carriage from the interior walls of the casing, means for latching the chassis in seiected positions of angular adjustment on the carriage, handle means at the front of the panel for moving the chassis constructed for prehensien by the fingers of a grasping hand and manipulable means for ccntrolling the latching means exposed at the front of the panel within range of a digit of such hand.

7. A radio apparatus comprising a, casing, a, panel forming a closure theref0r, a chassis projecting from the panel, trunnions on the chassis, a carriage having bearings for said trunnions thereby to support the chassis, telescopic extension devices for supporting the carriage from the interior walls of the casing, a sector on the carriage adjacent a trunmon, a, sliding boit on the chassis lockingly engaging the, sector in one position of the bolt, a, handle on the panel for moving the chassis, a rotary shaft projecting rearwardly from the panel and having finger piece at the front of the panel for turning the same, and means connecting shaft and boit to reciprocate the latter on turning of the former.

8. A radio apparatus comprising a chassis and a casing with which the chassis is associated through an intermediate slide in the manner of an extension drawer, a panel carried by the chassis forming a, closure for the casing, latches between panel and casing, a 1atch for holding the chassis in eXtended position, a, handle on the front of the panel for moving the chassis, mechanism for retracting both the first and second :nentioned latches and actuating means therefor in close spacial relation to the handle providing for their actuation by the fingers of a hand graspme a handle without release of the latter.

9. A radio apparatus comprising a chassis and a casing with which the chassis is connected through an intermediate slide in the manner 01 an extension drawer, means whereby the chassis is mounted on the slide for swinging adjustment about a horizontal axis When withdrawn from the casing, a panel carried by the chassis forming a closure for the casing, latches between the panel and casing, a latch for holding the chassis in extended position, and a latch for retaining the chassis in fixed position 01 angular adjustment about said horizontal axis, a handle on the front of the panel for moving the chassis, mechanism for retracting both the first and second mentioned latches and actuating means thereior in close spacial relation to the handle providing for their actuation by the fingers of a hand grasping a handle without release of the latter.

10. A radio apparatns comprising a casing and a chassis and panel associated with the casing in the manner of a drawer and drawer front respectively with a drawer casing, handles on the panel for moving the chassis in and out relatively to the casing, a abutment within the casine, a pushing element on the rear of the panel cooperating with the abutment to start the chassis out from the casing and a lever in close spacial relation to the handle providing for its operation by the fin- 1 1 gers of a hand clasping the handle without release of the latter, said lever being connected to said pshing element for operating the same.

11. In a radio apparatus a, sheet metal casing cf generally rectangular section having an open end, a panel forming a closure for said end having a flange opposing the wall of the casing edge to edge, at 1east one of said edges having projecting portions adapted to enter beneath and closely fit within the other, a chassis projecting from the panel and slidably received in the casing, an abutment within the casing, a pushing element on the rear of the panel cooperating with the abutment to start the chassis out from the casing, and a lever in close spacia1 relation to the handle providing for its operation by the fingers of a hand clasping the handle without release of the latter, said lever being connected to said pushing clement for operating the same.

12. In 3, radio apparatus a sheet metal casing of generally rectangular section having an open end, a panel forming a closure for said end having a flange opposing the wall of the casing edge t edge, a chassis projecting from the panel and slidably received in the casing and relatively staggered fingers secured to the inner surface of the flange and case respectively having beve1led ends to pass beneath the opposing member for aligning and positioning said edges.

13. In a radio apparatus a sheet metal casing of generally rectangular section having an open end, a panel forming a closure for said end having a flange opposing the wall of the casing edge tu edge, a chassis projecting from the panel and slidabl received in the casing and relatively staggered fingers secured to the inner surfaces of the flange and case respectivelv having bevelled ends to pass beneath the opposing member for aligning and positioning said edges, and yieldable contact arms in the path of at least certain of the fingers to establish electrical connecticn between the parts in the closed position.

14. Aradio apparatns comprising a chassis and a casing with which the chassis is associated in the manner of a drawer, a panel carried by the chassis forming a closure for the casing, multiple bolts at the back of the panel for locking it closed, a handle on the panel front having a bar spaced therefrom to be encircled by the grasping fin gers of the hand, a lever pivoted at one end of the bar to overlie the outer surface of the same in one position and when moved away therefrom adapted to receive on its under side the ball of the thumb of the grasping hand t0 press the lever away*frcm the bar and transmitting means between the lever and bolts to retract the latter when the leveris so pressed.

15. A radio apparatns comprising a chassis and a casing with which the chassis is associated in the manner of a drawer, a panel carried by the chassis forming a closure for the casing, multiple bolts at the back of the panel for locking it closed, a handle on the panel front having a bar spaced therefrom to be encircled by the grasping fingers Of the hand, a lever pivoted at one end of the bar .to overlie the outer surface of the same in one position, a catch for holding the lever in such one position, a, thumb button for releasing the catch located in range of the thumb of the grasping hand as the hand retains its hold of the bar, said lever when moved from the bar adapted to receive on its under side the ball of the thumb of the grasping hand t0 press the lever away from the bar and transmitting means between the lever 12 and bolts to retract the latter when the lever is so pressed.

16. A radio apparatus comprising a casing, a panel formirig a front closure therefor, a. chassis projecting from the panel, extension slide mechanism for supporting the chassis from the interior walls of the casirig, the casing having an opening remote from its front end, an auxiliary casing having an open side fitted to said opening, latches within the casing for securing the auxiliary casing, and mechanism within the casing for operating the latches comprising an operating portion adjacent the front of the casing and accessible from the front when the chassis is extended.

17. A radio apparatus comprising a casing, a panel forming a front closure therefor, a chassis projecting from the panel, extension Slide mechanism for supporting the chassis from the interior walls of the casing and on which said chassis is pivoted, the casing having an opening remote from its front end, an auxiliary casing having an open side fitted to said opening, latches within the casing for securing the auxiliary casing, mechanism within the casing for'operating the latches comprising an cperating portion adjacent the front of the casing and accessible from the front when the chassis is extended, and means for locking the chassis when extended from the casing in an upwardly and outwardly slanting position to provide a clearance between the top of the same and the top end of the casng for access to said portion.

18. A radio apparatus comprising a casing, a panel forming a front closure therefcr, a chassis projecting from the panel, extension slide mechanism for supporting the chassis from the inte rior walls of the casing, the casing having an opening remote from its front end, an auxiliary casing having an open side with an outwardly extending flange underlying the inner margin of the opening, latches on the interior wall of the casing to overlie said fiange to position the auxiliary casing, and mechanism within the casing for operating the latches comprisng an operating portion adjacent the front of the casing and accessible from the front when the chassis is extended.

19. A radio apparatus comprising a casing, a panel forming a front closure theref0r, a chassis projecting from the panel, extension slide mechanism for supporting the chassis from the interior walls of the casing, the casing having an opening remote from its front end, an auxiliary casing having an open side with an ontwardly extending notched flange underlying the inner margin of the opening, latch bars slidably mounted on the inner wall of the casing having portions adapted in one position to pass through the notches and in another to overlie the flange portiens between the notches, a shaft having driving connecticn to the bars for reciprocating the same and extendng along the interior of the casing wall to a point adjacent the front of the same and there having means for turning the same.

20. A radio apparatus comprising a casing, a panel forming a front closure therefcr, a chassis projecting from the panel, extension slide mechanism for supporting the chassis from the interior walls of the casing, the casing having an opening remote from its front end, an auxiliary casing having an open side with an outwardly extending notched flange underlying the inner margin of the opening, latch bars slidably mounted on the inner wall of the casing having portions adapted in one position to pass through the notches and REFEREN CES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 321,078 Birckhead June 30, 1885 Number 14 Name Date Gilzinger Feb. 15, 1887 Lawson May 24, 1910 Severance May 29, 1917 Collings Sept. 25, 1917 0berst June 25, 1929 Godfrey July 12, 1932 Hayden Jan. 21, 1936 Hay June 1, 1937 Yost Mar. 8, 1938 Hay Sept. 5, 1939 Doescher June 11, 1940 Young et al July 21, 1942 Hultgren et al. Apr. 3, 1945 

